Pyrometer/exhaust temp

[8buck]

Any idea how hot the pipes, right off the motor, should be at an idle, and how about after a good wot run? I know they will be hotter lean and cooler rich but I wonder if there is an ideal temp. I've done the whole plug chop thing and they look great, but, if one is a LITTLE off from the other I should be able to tell from the exhaust temps (one pipe a bit hotter than the other) and dial them in to match, correct?

 

PS: I have Power Jets to tweek the top end.

[dawarriorman]

If I remember right, I think right around 1200 up to 1300 F, although I wouldn't take my word on that. (that would be max temp)

Edited June 2, 2006 by dawarriorman

[superdave]

I have always been told that 1200 is where you want to run exhaust temps..., but some will run them hotter-leaner to get performance out of the motor....Leaner is also sooner on a rebuild...I ran a shifter kart motor at 1200 all season and my friend even did real well at nationals 2nd place, when we took the motor out and sent it to Swedtech they where surprised how good it looked after a season. at Nationals the swedtech motor guys ran it up to 1300, but at that point engine longetivity is not a player.....D

[fastcar01]

It really is different for every machine. The pipe manufacturer determines what it should be and even that is approx, based on the location the probe is located. The pipe manf. should give a distance that the probe should be from the piston skirt. The best way to figure out what it should be, is to hook up the gages, then make a WOT pass and kill it while moving. Note the temp readings, then read the plugs. If the plugs look good, you know what temp to run it at. Don't just use a figure of 1200 or so. On my sled I use D&D pipes and they recommend a WOT temp of aound 1150-1175. At this temp my plugs look perfect. Really at idle it doesn't matter what it is. Depending on your carbs, you may have a lean spot in the midrange, but this is a carb tuning issue. AC tripples are notorious for running hot in the midrange, especially when you big bore them, needle jets are too small. I know I would have melted mine without the gages.

 

So bottom line is you check plugs and wash to find where you run best, then use that temp as your baseline. Do not use the temp as a rule, becasue there isn't one, each machine is different.

[jankab]

It really is different for every machine. The pipe manufacturer determines what it should be and even that is approx, based on the location the probe is located. The pipe manf. should give a distance that the probe should be from the piston skirt. The best way to figure out what it should be, is to hook up the gages, then make a WOT pass and kill it while moving. Note the temp readings, then read the plugs. If the plugs look good, you know what temp to run it at. Don't just use a figure of 1200 or so. On my sled I use D&D pipes and they recommend a WOT temp of aound 1150-1175. At this temp my plugs look perfect. Really at idle it doesn't matter what it is. Depending on your carbs, you may have a lean spot in the midrange, but this is a carb tuning issue. AC tripples are notorious for running hot in the midrange, especially when you big bore them, needle jets are too small. I know I would have melted mine without the gages.

 

So bottom line is you check plugs and wash to find where you run best, then use that temp as your baseline. Do not use the temp as a rule, becasue there isn't one, each machine is different.

I run mine at 1200 for a max temp, haven't burned it down yet

[fastcar01]

I run mine at 1200 for a max temp, haven't burned it down yet

 

Is that across the board or WOT? I know mine will run 1100 WOT, and part throttle it will hit over 1250. Like I sadi just check you plugs and the piston wash.

[snowfoxsx]

how far from the cylinders do you place the probes on a banshee?

[fastcar01]

how far from the cylinders do you place the probes on a banshee?

 

Well I am guessing it is like snowmobiles, it is different depending on what pipes you have.